The present invention relates to an interface system for an electronic computer, and more particularly to an interface system disposed between a service processing unit for resetting operations undertaken within an electronic computer and for control of an operator's console unit and an input/output channel unit.
FIG. 3 shows the general construction of the inside of a typical conventional electronic computer. In the drawing are shown an electronic computer designated by reference numeral 1, a central processing unit (CPU) 2, a main memory 3, an input/output channel unit 4, an individual input/output channel 5, a service processing unit 6, an operator's console unit serving as a console input/output device 7, an operator's console control unit 8 which is incorporated in the service processing unit 6, an input/output interface 9 adapted to connect the input/output channel 5 and the input/output device, a serial interface 10 for connecting the input/output channel unit and the service processing unit 6, and a channel adapter unit 11 for connecting the input/output channel 5 and the operator's console control unit 8. FIG. 4 shows a typical conventional mechanism in which a group of latches comprising the input/output channel unit 4 can be at choice read and written via the service processing unit 6. In the drawing are shown an individual latch designated by reference numeral 12A which comprises a shift register of the input/output channel unit, a ring transmitting path 12B for connecting the latches, a ring transmitting terminal select unit 13 for selecting one of the plurality of ring transmitting paths to send data, a ring receiving terminal select unit 14 for selecting one of the ring transmitting paths to receive data, and a shift register 15.
The operation of such an interface system will now be explained.
With an arrangement such as that noted above, when an input/output operation is conducted at the operator's console unit 7 for processing by the CPU2, the CPU2 first operates to activate an input/output operation at the input/output channel unit 4, and then said input/output channel unit 4 selects corresponding input/output channel 5 and activates an input/output operation at the operator's console control unit 8 by way of the input/output interface 9 and the channel adapter unit 11. The input/output operation at the operator's console unit 7 is commenced in this way. It is also seen that a data transfer operation may take place with a path consisting of the operator's console unit 7, the operator's console control unit 8, the channel adapter unit 11, the input/output interface 9, the input/output channel 5, and the main memory 3, in that order or in the opposite order.
On the other hand, when the service processing unit 6 serves to read or write the group of latches which comprise the input/output channel unit 4 for the purpose of a resetting operation or the like, the serial interface 10 will be used. According to the arrangement shown in FIG. 4, when reading a latch 12A, a ring transmitting path 12B may be selected by way of the ring receiving terminal select unit 14, applying shift clocks to serially transfer the content of the latch 12A to the shift register 15. Also, when writing into the latch 12A, a ring transmitting path 12B may be selected by way of the ring transmitting terminal select unit 13 while having data prepared in advance to be written in the shift register 15, applying shift clocks to serially transfer the content of the shift register 15 to the latch 12A.
With such a typical construction of the conventional computer interface system as that noted above, it is essential to provide an interface circuit such as a channel adapter unit or the like as in other input/output devices between an operator's console control unit and an input/output channel unit, which accordingly, should then be connected to an input/output interface cable.
The present invention is essentially directed to resolution of the above mentioned problems, and it is an object of the invention to provide an improved interface system which allows a channel adapter unit and an input/output interface cable for the operator's console control unit which is incorporated in the service processing unit to be dispensed with.